US3715638A - Temperature compensator for capacitive pressure transducers - Google Patents
Temperature compensator for capacitive pressure transducers Download PDFInfo
- Publication number
- US3715638A US3715638A US00112359*[A US3715638DA US3715638A US 3715638 A US3715638 A US 3715638A US 3715638D A US3715638D A US 3715638DA US 3715638 A US3715638 A US 3715638A
- Authority
- US
- United States
- Prior art keywords
- temperature
- thin film
- resistor
- pressure transducer
- kind described
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
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Classifications
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L9/00—Measuring steady of quasi-steady pressure of fluid or fluent solid material by electric or magnetic pressure-sensitive elements; Transmitting or indicating the displacement of mechanical pressure-sensitive elements, used to measure the steady or quasi-steady pressure of a fluid or fluent solid material, by electric or magnetic means
- G01L9/0082—Transmitting or indicating the displacement of capsules by electric, electromechanical, magnetic, or electromechanical means
- G01L9/0086—Transmitting or indicating the displacement of capsules by electric, electromechanical, magnetic, or electromechanical means using variations in capacitance
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L9/00—Measuring steady of quasi-steady pressure of fluid or fluent solid material by electric or magnetic pressure-sensitive elements; Transmitting or indicating the displacement of mechanical pressure-sensitive elements, used to measure the steady or quasi-steady pressure of a fluid or fluent solid material, by electric or magnetic means
- G01L9/0041—Transmitting or indicating the displacement of flexible diaphragms
- G01L9/0072—Transmitting or indicating the displacement of flexible diaphragms using variations in capacitance
- G01L9/0075—Transmitting or indicating the displacement of flexible diaphragms using variations in capacitance using a ceramic diaphragm, e.g. alumina, fused quartz, glass
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L9/00—Measuring steady of quasi-steady pressure of fluid or fluent solid material by electric or magnetic pressure-sensitive elements; Transmitting or indicating the displacement of mechanical pressure-sensitive elements, used to measure the steady or quasi-steady pressure of a fluid or fluent solid material, by electric or magnetic means
- G01L9/12—Measuring steady of quasi-steady pressure of fluid or fluent solid material by electric or magnetic pressure-sensitive elements; Transmitting or indicating the displacement of mechanical pressure-sensitive elements, used to measure the steady or quasi-steady pressure of a fluid or fluent solid material, by electric or magnetic means by making use of variations in capacitance, i.e. electric circuits therefor
- G01L9/125—Measuring steady of quasi-steady pressure of fluid or fluent solid material by electric or magnetic pressure-sensitive elements; Transmitting or indicating the displacement of mechanical pressure-sensitive elements, used to measure the steady or quasi-steady pressure of a fluid or fluent solid material, by electric or magnetic means by making use of variations in capacitance, i.e. electric circuits therefor with temperature compensating means
Definitions
- ABSTRACT A pressure transducer of the capacitor type having a body of dielectric material has a thin film resistor deposited on the body for sensing the temperature of the body.
- the resistor is of a material having a suitable temperature coefficient of resistivity to provide a signal corresponding to the temperature of the body for temperature correction.
- the invention relates to temperature compensation and more particularly to temperature compensation for capacitive type pressure transducers.
- the magnitude of error caused by temperature changes of such transducers mainly depends upon the materials of construction, the design details and the operating temperature range. In most cases when high 'accuracy is required over large temperature excursions, the variation in elastic constant (Youngs Modulus) of the transducer material is the most significant factor contributing to error.
- a direct approach for correcting this error is to measure the temperature of the transducer by electrical means and apply a correction voltage to the capacitor output.
- the main difficulty heretofore in sensing the transducer temperature is that unwanted stresses are created on the sensitive deflecting members of the transducer.
- One object of the present invention is to sense the temperature of a pressure transducer without creating unwanted stresses on the sensitive deflecting members of the transducer.
- Another object of the invention is to provide a thin film resistor on the sensitive deflecting members of the transducer.
- Another object is to deposit the film resistor on the transducer during one of the regular steps in fabricating signal corresponding to the temperature of the body.
- the thin film resistor preferably is deposited on the body simultaneously with a thin film electrostatic shield of the same material as the thin film resistor.
- FIG. 1 is a top view of a capacitive type pressure transducer having a thin film resistor deposited thereon in accordance with the invention.
- FIG. 2 is a transverse vertical section taken on the line 2-2 of FIG. 1.
- FIG. 3 is a schematic diagram of a bridge circuit including thin film resistors for providing temperature compensating signals.
- FIG. 4 is a schematic diagram of a bridge circuit including the pressure transducer capacitors and thin film resistors for providing a temperature compensated pressure signal.
- the pressure transducer has a body 1 of dielectric material such as glass or quartz.
- the body is formed of a pair of shallow cup-like members 3, 5 sealed together to provide. a chamber 7 therein which may be evacuated in a 'well known manner.
- Capacitor plates 9, 11 are deposited on the opposing inner faces of members 3, 5 and form a capacitor which provides a signal corresponding to the sensed pressure applied exteriorly of body 1.
- Suitable connectors l3, 15 may be provided on capacitor plates 9, 11 for connection in an electrical circuit.
- a thin film metallic coating 17 is provided on the external surfaces of body 1 to provide an electrostatic shield.
- the temperature sensors in the present invention are thin film resistors 19, 21 of the order of a few hundred Angstroms in thickness which are deposited on the pressure sensitive deflecting members of body 1, preferably simultaneously with the electrostatic shield by vacuum evaporation or sputtering.
- the resistors are insulated electrically from the electrostaticshield by using stencil marks or by etching after deposition.
- the resistors preferably are of a material, such as nickel or platinum, which has a relatively high temperature coefficient of resistivity for providing a signal corresponding to the temperature of body 1.
- the thin film metallic coating 17 may also be of the same material so that the thin film resistors 19, 21 and thin film metallic coating 17 can be deposited simultaneously.
- Resistors 19, 21 have suitable terminals 23, 25, 27, 29 at their ends for connection in a circuit as described hereinafter.
- Resistors l9 and 21 may be connected in opposite legs of a bridge circuit as shown in FIG. 3 at R,, R and their resistances are compared with the resistances of reference resistors R, connected in the other opposite legs of the bridge circuit.
- a suitable voltage supply is connected across opposing terminals of the bridge circuit and a signal corresponding to the resistance of resistors R, and R is provided on the other two opposing terminals of the bridge circuit in the usual manner.
- the temperature compensating signal may be used in any well known manner for temperature correcting the capacitor signal corresponding to pressure.
- FIG. 4 One suitable arrangement for correcting the capacitor signal for temperature variations is shown in FIG. 4 wherein resistors R and R are connected in one leg of a bridge circuit and a reference resistor R, is connected in a second leg of the bridge circuit.
- the pressure sensing capacitor C is connected in a third leg of the bridge and a reference capacitor C, is connected in a fourth-leg of the bridge.
- a suitable voltage supply is connected across the bridge to opposing terminals between the legs with the resistors and between the legs with the capacitors and a temperature compensated pressure signal is provided across the other two opposing terminals of the bridge.
- a pressure transducer having thin film resistors deposited on the sensitive deflecting members in accordance with the invention provides a temperature compensated pressure signal without creating unwanted stresses on the sensitive deflecting members and the pressure signal is accurately compensated for variations in temperature.
- the thin film resistors can be deposited on the transducer during one of the regular steps in fabricating the transducer by vacuum evaporation or sputtering.
- a pressure responsive capacitor comprising pressure deflectable supporting means with electrical conducting means on said supporting means, the conducting means having non-solid means therebetween forming the dielectric of the capacitor, a thin film resistor deposited on said supporting means for sensing the temperature of the supporting means, the resistor being of a material having a relatively high temperature coefficient of resistivity for providing a signal corresponding to the the temperature of the supporting means.
- a pressure transducer of the kind described in claim 1 in which the thin film resistor is deposited on the body by vacuum evaporation.
- a pressure transducer of the kind described in claim I having means for connecting the resistor in an electrical circuit.
- a pressure transducer of the kind described in claim 1 in which a thin film electrostatic shield of the same material as the thin film resistor is deposited on the body simultaneously with the thin film resistor and is electrically insulated therefrom.
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- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Ceramic Engineering (AREA)
- Measuring Fluid Pressure (AREA)
Abstract
A pressure transducer of the capacitor type having a body of dielectric material has a thin film resistor deposited on the body for sensing the temperature of the body. The resistor is of a material having a suitable temperature coefficient of resistivity to provide a signal corresponding to the temperature of the body for temperature correction.
Description
United States Patent [191 Polye [54] TEMPERATURE COMPENSATOR FOR CAPACITIVE PRESSURE TRANSDUCERS [75] Inventor: William Ronald Polye, River Edge,
[73] Assignee: The Bendix Corporation [22] Filed: May 10, 1971 [21] App1.No.: 112,359
[52] U.S. Cl. ..317/247, 317/246, 317/256, 338/25, 338/334 [51] Int. Cl. ..H0ly 3/24 [58] Field of Search ..3 l7/246, 247, 253, 256; 73/398 C; 338/25, 334
[56] References Cited UNITED STATES PATENTS 2,725,548 11/1955 Harris "73/398 C Feb.6,1973
2,940,035 6/1960 Lefkowitz ..317/256 X 3,253,207 5/1966 Fauch 3,405,559 10/1968 Moffatt ..3 17/240 OTHER PUBLICATIONS Dummor Fixed Resistors, Pitman & Sons, London 1967, pp. 41, 56 & 57.
Primary Examiner-E. A. Goldberg 1 Attorney-S, H. Hartz and Plante, Hartz, Smith and Thompson [57] ABSTRACT A pressure transducer of the capacitor type having a body of dielectric material has a thin film resistor deposited on the body for sensing the temperature of the body. The resistor is of a material having a suitable temperature coefficient of resistivity to provide a signal corresponding to the temperature of the body for temperature correction.
8 Claims, 4 Drawing Figures PATENTEDFEB slsza 3.715638 INVENTOR.
W'///am Pam/a Pa/ye R TTORNE Y TEMPERATURE COMPENSATOR FOR CAPACITIVE PRESSURE TRANSDUCERS The invention relates to temperature compensation and more particularly to temperature compensation for capacitive type pressure transducers.
The magnitude of error caused by temperature changes of such transducers mainly depends upon the materials of construction, the design details and the operating temperature range. In most cases when high 'accuracy is required over large temperature excursions, the variation in elastic constant (Youngs Modulus) of the transducer material is the most significant factor contributing to error. A direct approach for correcting this error is to measure the temperature of the transducer by electrical means and apply a correction voltage to the capacitor output. The main difficulty heretofore in sensing the transducer temperature is that unwanted stresses are created on the sensitive deflecting members of the transducer.
One object of the present invention is to sense the temperature of a pressure transducer without creating unwanted stresses on the sensitive deflecting members of the transducer.
Another object of the invention is to provide a thin film resistor on the sensitive deflecting members of the transducer.
Another object is to deposit the film resistor on the transducer during one of the regular steps in fabricating signal corresponding to the temperature of the body..
The thin film resistor preferably is deposited on the body simultaneously with a thin film electrostatic shield of the same material as the thin film resistor.
These and other objects and advantages of the invention are pointed out in the following description in terms of the embodiment thereof which is shown in the accompanying drawing. It is to be understood, however, that the drawing is for the purpose of illustration only and is not a definition of the limits of the invention, reference being had to the appended claims for this purpose.
In the drawing,
FIG. 1 is a top view of a capacitive type pressure transducer having a thin film resistor deposited thereon in accordance with the invention.
FIG. 2 is a transverse vertical section taken on the line 2-2 of FIG. 1.
FIG. 3 is a schematic diagram of a bridge circuit including thin film resistors for providing temperature compensating signals.
FIG. 4 is a schematic diagram of a bridge circuit including the pressure transducer capacitors and thin film resistors for providing a temperature compensated pressure signal.
Referring to the drawing which shows a pressure transducer having novel thin film resistors constructed according to the invention, the pressure transducer has a body 1 of dielectric material such as glass or quartz. The body is formed of a pair of shallow cup-like members 3, 5 sealed together to provide. a chamber 7 therein which may be evacuated in a 'well known manner. Capacitor plates 9, 11 are deposited on the opposing inner faces of members 3, 5 and form a capacitor which provides a signal corresponding to the sensed pressure applied exteriorly of body 1. Suitable connectors l3, 15 may be provided on capacitor plates 9, 11 for connection in an electrical circuit. To avoid the introduction of active capacitance in the electrical measurements a thin film metallic coating 17 is provided on the external surfaces of body 1 to provide an electrostatic shield.
The temperature sensors in the present invention are thin film resistors 19, 21 of the order of a few hundred Angstroms in thickness which are deposited on the pressure sensitive deflecting members of body 1, preferably simultaneously with the electrostatic shield by vacuum evaporation or sputtering. The resistors are insulated electrically from the electrostaticshield by using stencil marks or by etching after deposition. The resistors preferably are of a material, such as nickel or platinum, which has a relatively high temperature coefficient of resistivity for providing a signal corresponding to the temperature of body 1. For convenience, the thin film metallic coating 17 may also be of the same material so that the thin film resistors 19, 21 and thin film metallic coating 17 can be deposited simultaneously. Resistors 19, 21 have suitable terminals 23, 25, 27, 29 at their ends for connection in a circuit as described hereinafter.
Resistors l9 and 21 may be connected in opposite legs of a bridge circuit as shown in FIG. 3 at R,, R and their resistances are compared with the resistances of reference resistors R, connected in the other opposite legs of the bridge circuit. A suitable voltage supply is connected across opposing terminals of the bridge circuit and a signal corresponding to the resistance of resistors R, and R is provided on the other two opposing terminals of the bridge circuit in the usual manner. The temperature compensating signal may be used in any well known manner for temperature correcting the capacitor signal corresponding to pressure.
One suitable arrangement for correcting the capacitor signal for temperature variations is shown in FIG. 4 wherein resistors R and R are connected in one leg of a bridge circuit and a reference resistor R, is connected in a second leg of the bridge circuit. The pressure sensing capacitor C, is connected in a third leg of the bridge and a reference capacitor C, is connected in a fourth-leg of the bridge. A suitable voltage supply is connected across the bridge to opposing terminals between the legs with the resistors and between the legs with the capacitors and a temperature compensated pressure signal is provided across the other two opposing terminals of the bridge.
A pressure transducer having thin film resistors deposited on the sensitive deflecting members in accordance with the invention provides a temperature compensated pressure signal without creating unwanted stresses on the sensitive deflecting members and the pressure signal is accurately compensated for variations in temperature. The thin film resistors can be deposited on the transducer during one of the regular steps in fabricating the transducer by vacuum evaporation or sputtering.
What is claimed is:
l. A pressure responsive capacitor comprising pressure deflectable supporting means with electrical conducting means on said supporting means, the conducting means having non-solid means therebetween forming the dielectric of the capacitor, a thin film resistor deposited on said supporting means for sensing the temperature of the supporting means, the resistor being of a material having a relatively high temperature coefficient of resistivity for providing a signal corresponding to the the temperature of the supporting means.
2. A pressure transducer of the kind described in claim 1 in which the thin film resistor is deposited on the body by vacuum evaporation.
3. A pressure transducer of the kind described in claim 1 in which the thin film resistor is deposited on the body by sputtering.
4. A pressure transducer of the kind described in claim I having means for connecting the resistor in an electrical circuit.
5. A pressure transducer of the kind described in claim 1 in which the dielectric material is quartz.
6. A pressuretransducer of the kind described in claim 1 in which the material of the resistor is nickel.
7. A pressure transducer of the kind described in claim 1 in which the material of the resistor is platinum.
8. A pressure transducer of the kind described in claim 1 in which a thin film electrostatic shield of the same material as the thin film resistor is deposited on the body simultaneously with the thin film resistor and is electrically insulated therefrom.
Claims (7)
1. A pressure responsive capacitor comprising pressure deflectable supporting means with electrical conducting means on said supporting means, the conducting means having non-solid means therebetween forming the dielectric of the capacitor, a thin film resistor Deposited on said supporting means for sensing the temperature of the supporting means, the resistor being of a material having a relatively high temperature coefficient of resistivity for providing a signal corresponding to the the temperature of the supporting means.
2. A pressure transducer of the kind described in claim 1 in which the thin film resistor is deposited on the body by vacuum evaporation.
3. A pressure transducer of the kind described in claim 1 in which the thin film resistor is deposited on the body by sputtering.
4. A pressure transducer of the kind described in claim 1 having means for connecting the resistor in an electrical circuit.
5. A pressure transducer of the kind described in claim 1 in which the dielectric material is quartz.
6. A pressure transducer of the kind described in claim 1 in which the material of the resistor is nickel.
7. A pressure transducer of the kind described in claim 1 in which the material of the resistor is platinum.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US11235971A | 1971-05-10 | 1971-05-10 |
Publications (1)
Publication Number | Publication Date |
---|---|
US3715638A true US3715638A (en) | 1973-02-06 |
Family
ID=22343484
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US00112359*[A Expired - Lifetime US3715638A (en) | 1971-05-10 | 1971-05-10 | Temperature compensator for capacitive pressure transducers |
Country Status (7)
Country | Link |
---|---|
US (1) | US3715638A (en) |
JP (1) | JPS5528335B1 (en) |
CA (1) | CA923631A (en) |
DE (1) | DE2221062C3 (en) |
FR (1) | FR2139401A5 (en) |
GB (1) | GB1319218A (en) |
IT (1) | IT955321B (en) |
Cited By (37)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3748571A (en) * | 1972-09-07 | 1973-07-24 | Kulite Semiconductors Products | Pressure sensitive transducers employing capacitive and resistive variations |
US3787764A (en) * | 1971-12-03 | 1974-01-22 | Atomic Energy Commission | Solid dielectric capacitance gauge for measuring fluid pressure having temperature compensation and guard electrode |
DE2459612A1 (en) * | 1973-12-26 | 1975-07-10 | Bendix Corp | CAPACITIVE PRESSURE TRANSDUCER |
US3991285A (en) * | 1973-10-01 | 1976-11-09 | U.S. Philips Corporation | Microphone having an electrostatic cartridge having a structural electrical resistor |
FR2344006A1 (en) * | 1976-03-12 | 1977-10-07 | Kavlico Corp | CAPACITIVE PRESSURE TRANSDUCER AND METHOD FOR MANUFACTURING SUCH A TRANSDUCER |
US4084438A (en) * | 1976-03-29 | 1978-04-18 | Setra Systems, Inc. | Capacitive pressure sensing device |
DE2820478A1 (en) * | 1977-05-10 | 1978-11-16 | Setra Systems Inc | CAPACITIVE PRESSURE SENSOR CONVERTER AND METHOD FOR ITS MANUFACTURING |
US4151578A (en) * | 1977-08-01 | 1979-04-24 | Kavlico Corporation | Capacitive pressure transducer |
US4177496A (en) * | 1976-03-12 | 1979-12-04 | Kavlico Corporation | Capacitive pressure transducer |
US4204244A (en) * | 1978-01-23 | 1980-05-20 | Motorola, Inc. | Electromechanical pressure transducer |
FR2442966A1 (en) * | 1978-11-30 | 1980-06-27 | Bosch Gmbh Robert | Combustion engine inlet manifold pressure and temp. meter - contains thin film sensors and supply and measurement circuits on common substrate |
EP0018283A1 (en) * | 1979-04-16 | 1980-10-29 | The Bendix Corporation | Pressure sensor |
US4238662A (en) * | 1978-10-02 | 1980-12-09 | The Bendix Corporation | Pressure-sensing capacitor and method of trimming same |
US4238661A (en) * | 1978-10-02 | 1980-12-09 | The Bendix Corporation | Pressure-sensing capacitor and method of trimming same |
US4237989A (en) * | 1979-05-11 | 1980-12-09 | National Controls, Inc. | Capacitive load cell and method of manufacture |
US4262532A (en) * | 1979-09-13 | 1981-04-21 | General Electric Company | Pressure and temperature sensor |
US4388668A (en) * | 1976-03-12 | 1983-06-14 | Kaylico Corporation | Capacitive pressure transducer |
US4432007A (en) * | 1978-11-08 | 1984-02-14 | General Electric Company | Ultrasonic transducer fabricated as an integral part of a monolithic integrated circuit |
US4580157A (en) * | 1979-06-08 | 1986-04-01 | Fujitsu Limited | Semiconductor device having a soft-error preventing structure |
US4617606A (en) * | 1985-01-31 | 1986-10-14 | Motorola, Inc. | Capacitive pressure transducer |
DE3528520A1 (en) * | 1985-08-08 | 1987-02-19 | Bosch Gmbh Robert | PRESSURE SOCKET |
US4807477A (en) * | 1988-02-01 | 1989-02-28 | Motorola, Inc. | Capacitive temperature compensation for a pressure sensor |
US4814845A (en) * | 1986-11-03 | 1989-03-21 | Kulite Semiconductor Products, Inc. | Capacitive transducers employing high conductivity diffused regions |
US4982351A (en) * | 1986-05-05 | 1991-01-01 | Texas Instruments Incorporated | Low cost high precision sensor |
US5051937A (en) * | 1986-05-05 | 1991-09-24 | Texas Instruments Incorporated | Low cost high precision sensor |
US5097712A (en) * | 1989-09-28 | 1992-03-24 | Endress U. Hauser Gmbh U. Co. | Differential pressure measuring apparatus |
US5111698A (en) * | 1989-10-06 | 1992-05-12 | Endress U. Hauser Gmbh U. Co. | Differential pressure measuring apparatus |
US5155653A (en) * | 1991-08-14 | 1992-10-13 | Maclean-Fogg Company | Capacitive pressure sensor |
US5619476A (en) * | 1994-10-21 | 1997-04-08 | The Board Of Trustees Of The Leland Stanford Jr. Univ. | Electrostatic ultrasonic transducer |
WO1998057132A1 (en) * | 1997-06-12 | 1998-12-17 | Matulek Andrew M | Capacitive liquid level indicator |
US5894452A (en) * | 1994-10-21 | 1999-04-13 | The Board Of Trustees Of The Leland Stanford Junior University | Microfabricated ultrasonic immersion transducer |
US5982709A (en) * | 1998-03-31 | 1999-11-09 | The Board Of Trustees Of The Leland Stanford Junior University | Acoustic transducers and method of microfabrication |
US6548840B1 (en) * | 2000-04-03 | 2003-04-15 | Hrl Laboratories, Llc | Monolithic temperature compensation scheme for field effect transistor integrated circuits |
US20080228047A1 (en) * | 2007-01-19 | 2008-09-18 | Sierra Scientific Instruments, Inc. | Micro-remote gastrointestinal physiological measurement device |
US20110271772A1 (en) * | 2007-04-23 | 2011-11-10 | Sierra Scientific Instruments, Inc. | Suspended membrane pressure sensing array |
US20140022865A1 (en) * | 2011-04-13 | 2014-01-23 | Koninklijke Philips N.V. | Temperature compensation in a cmut device |
US10422713B2 (en) | 2014-12-19 | 2019-09-24 | Commissariat A L'energie Atomique Et Aux Energies Alternatives | Pressure sensor suited to measuring pressure in an aggressive environment |
Families Citing this family (16)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2442439A1 (en) * | 1978-11-24 | 1980-06-20 | Vaisala Oy | Aneroid capsule pressure gauge - has corrugated membranes of insulating material carrying flat capacitor plates to give capacitance change on pressure variation |
US4382247A (en) * | 1980-03-06 | 1983-05-03 | Robert Bosch Gmbh | Pressure sensor |
DE3008572C2 (en) * | 1980-03-06 | 1982-05-27 | Robert Bosch Gmbh, 7000 Stuttgart | Pressure cell |
DE3108300C2 (en) * | 1980-03-06 | 1986-05-28 | Robert Bosch Gmbh, 7000 Stuttgart | Pressure cell and process for its manufacture |
DE4000326C2 (en) * | 1990-01-08 | 1995-12-14 | Mannesmann Ag | Pressure sensor |
DE4011901A1 (en) * | 1990-04-12 | 1991-10-17 | Vdo Schindling | Capacitive pressure sensor with simultaneous temp. measurement - contains plates carrying electrodes, one carrying temp. dependent resistance path |
DE4031791A1 (en) * | 1990-10-08 | 1992-04-09 | Leybold Ag | CAPACITY GAUGE SENSOR |
DE9013959U1 (en) * | 1990-10-08 | 1990-12-13 | Leybold AG, 6450 Hanau | Sensor for a capacitance manometer |
DE4136995C2 (en) * | 1991-11-11 | 1996-08-08 | Sensycon Ind Sensorsyst | Capacitive pressure sensor |
US6484585B1 (en) | 1995-02-28 | 2002-11-26 | Rosemount Inc. | Pressure sensor for a pressure transmitter |
US5637802A (en) | 1995-02-28 | 1997-06-10 | Rosemount Inc. | Capacitive pressure sensor for a pressure transmitted where electric field emanates substantially from back sides of plates |
US6561038B2 (en) | 2000-01-06 | 2003-05-13 | Rosemount Inc. | Sensor with fluid isolation barrier |
WO2001050106A1 (en) | 2000-01-06 | 2001-07-12 | Rosemount Inc. | Grain growth of electrical interconnection for microelectromechanical systems (mems) |
US6508129B1 (en) | 2000-01-06 | 2003-01-21 | Rosemount Inc. | Pressure sensor capsule with improved isolation |
US6505516B1 (en) | 2000-01-06 | 2003-01-14 | Rosemount Inc. | Capacitive pressure sensing with moving dielectric |
US6520020B1 (en) | 2000-01-06 | 2003-02-18 | Rosemount Inc. | Method and apparatus for a direct bonded isolated pressure sensor |
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US2725548A (en) * | 1951-07-24 | 1955-11-29 | Harris Transducer Corp | Variable-capacitor transducer |
US2940035A (en) * | 1955-02-14 | 1960-06-07 | Gulton Ind Inc | Electrical component of ceramic combined with resistor applied to the surface thereof |
US3253207A (en) * | 1966-05-24 | Measuring apparatus | ||
US3405559A (en) * | 1966-11-07 | 1968-10-15 | United Aircraft Corp | Pressure transducer |
-
1971
- 1971-05-10 US US00112359*[A patent/US3715638A/en not_active Expired - Lifetime
- 1971-12-10 CA CA129881A patent/CA923631A/en not_active Expired
-
1972
- 1972-04-28 DE DE2221062A patent/DE2221062C3/en not_active Expired
- 1972-05-03 GB GB2057872A patent/GB1319218A/en not_active Expired
- 1972-05-09 IT IT24089/72A patent/IT955321B/en active
- 1972-05-10 JP JP4626072A patent/JPS5528335B1/ja active Pending
- 1972-05-10 FR FR7216661A patent/FR2139401A5/fr not_active Expired
Patent Citations (4)
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US3253207A (en) * | 1966-05-24 | Measuring apparatus | ||
US2725548A (en) * | 1951-07-24 | 1955-11-29 | Harris Transducer Corp | Variable-capacitor transducer |
US2940035A (en) * | 1955-02-14 | 1960-06-07 | Gulton Ind Inc | Electrical component of ceramic combined with resistor applied to the surface thereof |
US3405559A (en) * | 1966-11-07 | 1968-10-15 | United Aircraft Corp | Pressure transducer |
Non-Patent Citations (1)
Title |
---|
Dummor Fixed Resistors, Pitman & Sons, London 1967, pp. 41, 56 & 57. * |
Cited By (43)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3787764A (en) * | 1971-12-03 | 1974-01-22 | Atomic Energy Commission | Solid dielectric capacitance gauge for measuring fluid pressure having temperature compensation and guard electrode |
US3748571A (en) * | 1972-09-07 | 1973-07-24 | Kulite Semiconductors Products | Pressure sensitive transducers employing capacitive and resistive variations |
US3991285A (en) * | 1973-10-01 | 1976-11-09 | U.S. Philips Corporation | Microphone having an electrostatic cartridge having a structural electrical resistor |
DE2459612A1 (en) * | 1973-12-26 | 1975-07-10 | Bendix Corp | CAPACITIVE PRESSURE TRANSDUCER |
US4177496A (en) * | 1976-03-12 | 1979-12-04 | Kavlico Corporation | Capacitive pressure transducer |
FR2344006A1 (en) * | 1976-03-12 | 1977-10-07 | Kavlico Corp | CAPACITIVE PRESSURE TRANSDUCER AND METHOD FOR MANUFACTURING SUCH A TRANSDUCER |
US4388668A (en) * | 1976-03-12 | 1983-06-14 | Kaylico Corporation | Capacitive pressure transducer |
US4084438A (en) * | 1976-03-29 | 1978-04-18 | Setra Systems, Inc. | Capacitive pressure sensing device |
US4168518A (en) * | 1977-05-10 | 1979-09-18 | Lee Shih Y | Capacitor transducer |
DE2820478A1 (en) * | 1977-05-10 | 1978-11-16 | Setra Systems Inc | CAPACITIVE PRESSURE SENSOR CONVERTER AND METHOD FOR ITS MANUFACTURING |
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US20140022865A1 (en) * | 2011-04-13 | 2014-01-23 | Koninklijke Philips N.V. | Temperature compensation in a cmut device |
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Also Published As
Publication number | Publication date |
---|---|
CA923631A (en) | 1973-03-27 |
IT955321B (en) | 1973-09-29 |
GB1319218A (en) | 1973-06-06 |
DE2221062A1 (en) | 1972-11-23 |
JPS5528335B1 (en) | 1980-07-26 |
DE2221062C3 (en) | 1981-02-19 |
DE2221062B2 (en) | 1980-06-04 |
FR2139401A5 (en) | 1973-01-05 |
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